Field of the Invention
The present invention relates to an image decoding technique, and more specifically to a technique for decoding an image including an ROI (Region Of Interest).
Description of the Background Art
On JPEG (Joint Photographic Experts Group) 2000, coding and decoding of an image including an ROI is disclosed in INTERNATIONAL STANDARD ISO/IEC 15444-1 ITU-T RECOMMENDATION T.800 Information technology-JPEG 2000 image coding system: Core coding system Annex H—Coding of images with regions of interest. Specifically, a Max-shift method is disclosed. Further, disclosed is a method of developing an ROI on a wavelet plane.
In Japanese Translation of PCT International Application Publication No. 2001-520466 disclosed is a method of developing which of coefficients belongs to an ROI on the wavelet plane, though the type of the method is different from that used for a wavelet filter adopted in JPEG 2000. Further, an image processing technique on an image including an ROI is disclosed in Japanese Patent Application Laid Open Gazette No. 2006-203409, Japanese Translation of PCT International Application Publication No. 2002-528007, Japanese Patent Application Laid Open Gazette No. 2006-295299, Japanese Patent Application Laid Open Gazette No. 2006-279397, and Japanese Patent Application Laid Open Gazette No. 2011-166795.